Signaling system



G- A. LQQKE SZGNALING SYSTEM Filed 99?; '7. 1,924

Patented Feb. 22, 1 927.

to Nirnn STATES P rniar o FFicE,

enema a. more, or E ove, new roan, assl noa vre WESTERN ELE RIC COMPANY, mooneonnrnn, or new Yong, N. A. oonronarron or new YORK.

' SIGNALING sYs'rnM.

Application filed October 7, 1924. Seria1 -No. 7 12,152i.

This invention relates, in general, to signaling systems and more particularly :to submarine signaling "systems employing means forassociating the terminal apparatus with the cable.

in submarine cable-systems it is sometimes desirable to locate certain ofthe apparatus at the shore station where the submarine cable terminates, although for commercial reasons the messages are transmitted and received atya point some distance fromthe shore station but more accessible to the To facilitate testing in such a systemgit is advantageous 'to be able to con-' "trol the necessary switching mechanisms public.

;Erem either the shore station or the cable oiiice andrtoperform these switching operations in a certain sequence. More particu larly-is this true in the case of a long submarine cable which isoperated to alternate ly send and receive messages, since during the sending operatiom the dielectric of a long submarine cable absorbs an electrical charge of high value and it the ,sending apparatus is disconnected and the receiving apparatus immediately connected to the cable the dischargeioi this absorbed charge will resultin damage to the delicate receivif g mechanism. To prevent such damage, '11 is desirable after disconnecting the sendng apparatusuto ground the cable for a period oi time sufiicient to permit the majcrportion of this charge "to drain oil before the receiving mechanism is connected to the cable. No. 1,586 971' issued June 1,1926, there is disclosed method of protecting the receiving mechanism of sucha cable from injury during the switching operations. V

The principal object of the present invention is to enable either of two stations located at one end of a transmitting conductor (for example a long submarine ta le) to control signaling apparatus at both stations.

A further object". oi the invention is to perfoi-ln the switching operations automati cally and in such a. manner that the delicate ppa 1 no 'b cdamaged by excessive r s durin switching opera-. tions. M

In patent to Austen M. Curtis,

To accom lish these objects, and in ac cordance Wit 1 a featureof the invention the two stations located at one end of a sub' marine cable, arejoined by an operating loop and a control loop. Control means are provided at each of the stations for controlling the switching mechanisms operated at both stations and for associating the transmitting and recieving mechanisms located at both stations with the operating loop Inaccord'ance with another feature of the invention, during a certain time interval various switching operations are performed in a desired se uence'and at such ai speed as to preclude the possibility of damage to the receiving mechanism when it is connected to the cable. v

joined to the op rating station B- by means 7, of a cable compr singconductors oi an 7 operating loop and conductors 5, 601" a con- 'trol loop. At stationed is located the sending condenser K, shaping network N and the amplifier S, while at, theoperating station B is located the transmitter T and the receiving mechanism R. The conductor .7 of

cable C is associated either with sending condenser K or with receiving network N, or grounded by means of the contacts of polarized relay 8 A pair of polarized sen-:-

ing reflays9 and 10 have theirupper or operating windings connectedinseri'es witheach other and the operating loop conductors S,

a. ihe low rwindings of these relays are also connected-in series with each other and a source of energy 11 which is for the purpose ofbiasing the relays. By-the operation at these relays, the sending condenser K is cor ected to" either the positive or negative terminal of battery 12 V and it may be grounded through the armature of rel-av '10.

The op rat ng win 0f y 9 l 19 ill are associated with the operating loop by means of the lower contact springs of polarized relay 13. The input circuit of amplifier S is permanently connected to the network N as shown and the output circuit is connected through the lower contact springs of relay ll withihe operating loop 8, 4:. The lower right hand contact springs oi relay ll: control the operation o'l relay la, the right hand contact sprii'lgs of which are employed to connect the rectorin; network N to the cable conductor 7, while the left hand contact springs of this relay control the operation of relay 16 which is employed to short circuit amplifier S in the manner described in detail in the copending' Curtis application, referred to above. The upper winding of relay 16 is associated with battery 2 for th purpose of biasing the relay.

A spring controlled receiving key 1'? including the cam member 18 associated with battery 19 the positive terminal of which is grounded, and a similar sending key 20 provided with a cam member 2] connected. to the positive terminal oi? gz'roundeiil battery 22, are connected across the control loop conductors 5, 6. Indicating lamps 253 and 24 are associated with battery :25 by means of the upper contacts of relays i3 and let to indicate WllGiillGl the sending or receiving apparatus is connected to the line.

Atstation B a pair of spring; controlled keys 27 and 28 eorrcspondiinr to keys I)? and 20 and comprising res iiectively a cam member 29 connected to the negative terminal of grounded battery 30 and a cam member 31 connected to the positive tern'iinal of grounded battery 32 are associated with control. loop comluctors a. 6 for the purpose of? controlling the operation oi? polarized relays 35 and 36 which correspond to relays 13 and i l at station A. The upper contacts (ii there relays are adapted to control the ,com'ieclion oi indicating: lamps ST and 38 to the battery 40. The lower contacts oi rclay 36 are ada 'ited to crannact and disconnect the receiver It From the operating loop 3-), 4 and the lower contacts ot relar i?) in a Sili'lilill manner control the switching: oli ililllSlTlllfi'Gl' 'l to the oiieratilnr loop 3 This transmitter which is oil the stamlard tape controlled type adapted to connect the battery 41V to the lower or operating: \v'indinrr oi? transmittiuc relay 453 or the lower or operating: windimi oi tranamiltinc: relay l3 depending upon whether a dotor dash is to be transmitted. The intermediate windings of relays l2 and 43 are connected in series and to a battery iii For the purpose o if giving these relays the desired bias. The upper windings o't relays and el are conueeted in series and in cooperatioi'i with their contacts and the locking: lever provide undistorted impulses oil the inaxiniun'i length possible for the sending specs, {the contacts of these relays are adapted to connect the sending battery l6 through contacts of relay 35 operating loop 3, 4 contacts of relay ill to the upper or operating windings (it sending: relays 9 and 10 and thereby control the operation of relays l) and i0.

lVith the various relays-i opcrati-id in the dircction shown. the system is arranged for sending. As the transmitter T operated in the well known manner by means ot a perloratral tape positive or negative impulses corresponding to dots or dashes are transmitted from battery 4L6 and cause the (mcration of relays 9 and 10. In the posi tion shown for the armatnres o't relays 42 and 13, this operatiin, circuit may be traced :l'roin the positive terminal of battery 46 through outer contact and armature of relay 41? lower right hand contacts of relay 35, conductor 3 of the operating loop. lower right hand contacts of relay 13, the operating windings of relays 10 and 9 in order, lower left hand contacts of relay 15h conductor 4t. of the, operating loop, lower left hand contacts oi relay $55, armature and inner contact of relay 4-2 and back to the negative terminal of battery 16. The armatures of relays 9 and 10 are thus energized in such a manner that they eorrespoinl in position respectively with the armaturcs-i of transl'nitting relays 42 and 4:3. With relays 9 and 1.0 thus operated. the positive terminal of: sending battery 12 is connected through. the inner contact and armature of relay 10 to ground and the negative terminal, of battery 153 is connected through the outer contact and armature Of relay E) to the SCIKlll'lQ condenser K and thence through contact springs 50 and iii to conductor 7 of cable (l. A negative inipulse is thus, at this particular instant being: transmitted. over cable (l.

The receiving" mechanism R is disconnectcd from the operating;- loop by the open lower eoniiukts of relay 3G. The input circuit oi network W is short eircuitcd by means oi the right hand contact-i oil? relay l5. Jith the armature oi relay 'l.(l in the position shown a short circuit is placed across ainplliicr F1 in the manner prcviously rcl'crrcd lo. Ho long as control members 17. 20. 27 and remain unoperaliuh relays 4-52 and 43 will be operated in accordance with the pcriloralions in the tape being fed through transmitter T and will causc the armaturcs oi. relays 9 and i l to assume corrcspom'ling positions. thus rfoiiiici'liiiip positive battery ncgrativc ba tery or around to the cabin coaductor.

l l hcn it desired to chance from the smilinglo the receiving position, either hey 17 or QT is operated dependent upon whether the system is being controlled at station A or station l3. In the operat on of these keys. a handle is turned to wind up a spring member which in turn slowly rotates thecam member one complete :revo lution in a counter clockwise: direction. Assumingthat key 17 is operated, cainmem ber 18 momentarily en'gages its left hand :contaet member, thus completing a circuit from the negative terminal of -grounded battery 19 through can) member 18, left hand cont-act spring oi key 17 and thence in parallel through the windings of relay 8, arelay 13.and relay :to.ground. Upon the energizationof relay '8,.contact spring first zengages contact spring54, thereby connecting conductor 7 and oneterniinal of the sending condenser K simultaneously to localground. Upon further movement of the armature, contact sprlng 51 breaks engagement with contact'spring 50, thereby disconnecting the conductor 7 from sending condenser K and local. ground. .=lVl1en the movement of the armature .is-scoinpleted, contact spring .51 is-in engagement with springyfibithereby connecting conductor 7 through the, intermediate contacts .of relay 15,;toithesea:grou'ndGO. v Upon the operation-of relay 13, sending relays 9 and 10 are disconnected from .op erating loop 3, 4; by means of the lower contact springs of relay :13 and the upper left hand contact springsxof this relay :are closed, thereby completing a circuit. from battery QQ thrOugh the left hand contacts ant (receiving lamp 2% to ground,causingthis lainp'flto foe lit. Sending lamp, 28 also re mains litby current flowing from battery 25,

thrcugh vthe left hand upper contact of :Theopera relay 14; a11cl. lamp 23v to ground. tion of relay 3,5 atstatioipB, results in the tlj-ansn itting mechanism being disconnected fromthe line by the opening oft the lower contactsyof relay 35, and receiving lamp 38' is ;l.it by current flowing'troin battery 40 throughgthe upper lefthand contacts oi th s maining lit by current flowing from battery 10, through the upper left ,hand contact Then this con:

erounded batter -19 through cam- 18. r

hand contactot' ley 17 andthencein a,

parallel .path to ground through the ind: in s ot'relays 1 1 and 36. 'Upon the energ1 1on ot relay 36,.its armature is moved upper left hand relaycontacts and cldsing thcloiver contacts. The opening of the upper lett hand contacts results in extinguishing sendinglanip 37 and "theclos'ing o f-t e lmver ontactzsp lngs et .tlusreley onnects the ever the left hand cont-act, slowly.

spring iszengaged, a circuit is coin pletejdd trom the negative terminal t in therevcrse direction, thereby opening the ceiVing' mechanism R :to the operating loop 3, 4:. As relay. l t-operates, the upper left hand contacts are opened,=thus opening-the battery supply circuit and extinguishing sending lamp 528; the lowe-r left hand and intermediate contacts of relay lam-e closed connectingoperating loop 3, e tot-he output circuit of amplifier- S and the right hand movable contact spring engages its front contact thereby completing an energizing circuit for relay .15 from groundedbattery through .the right hand front contact lay 8 to which in turn is connected the-cable conductor 7, and as the movable spring of the intermediate contacts engages one ofthe right hand contactsprings, cable conductor 7 connected througlnthe contacts of relays 8 and 15 to. the upper input terminal of network N which at-:this instant is connected hand contacts of relay 15. Upon further inoveinento'l' the armature, the-rightrliand contactsof relay 15 are open thereby dis-. cennecting the sea ground from both the cable and the upper terminal of the net- Workr The left hand contacts of relay are then closed completing an energizing circuit for relay16 which ;may be traced.

from the negative terminal of grounded-battery SSthrough the-right hand front contacts of'relay 14, through the left hand contacts ofrelay 15 and the operating'ivindings of relay -16to ground. lay .16 moves to its alternate position, thus completing the finalgstep of ithe operation by removin the short circuit Pp-reviously placed across amplifier 'S.

The circuit as itnoW stands is completely arranged torieceiving impulses transmitted from the distant statioi'i over cable C. These impulses are filStllfHDSl'lllttGClitO the input cii'cuitiof amplifier Sand'a'fter being suitably amplified.- vare transmitted over operating loop?) at to the receiving mech-e nism The short circuit has been remove: from amplifier rendering it operative vand indie-ting lampsQ-ftahd 38 areilit indicating that thesystem .is in readiness to receive signals.

- When tis desired to again place the apparatus in condition "for transmitting 111G3- sages,either lzey 2O 28=- operated. asssuniinf that the former is .o aerated. can: 21

first engages the left hand contact of lrey- .20 thereby completing'the circuit from the positive terminal of grounded battery 22 through cain 21,-leiit hand centact :of key 20 and then in parallel. thrwln the windlegs: of lfilf ys The armature of re-.

3 6 9 sw et p 190 to the sea ground by meansof the right the armatnres of these relays to again as sumo the positions shown in the drawing. Upon the operation of relay 36, the lower cont-acts are again opened, thus disconnecting the receiving mechanism It from the operating loop 3, 4. Upon the closing of the upper leilit hand contacts oil relay the battery supply circuit for lamp 3? is again closed, causing this lamp to be lit while lamp 38 also remains lit. In a similar manner the operation of the upper contacts of relay 14 results in the lighting of lamp 23 at station A, lamp 2-}; remaining lit. The lower left hand and intermediate con tacts of relay let are opened thereby dis connecting the output circuit of anmlilicr S from operating loop 3, 4. The right hand back contacts of relay let being closed,

tacts of relay 1:) and the winding of relay The o 'ieration oi. relay lti to ground. connects a short circuit across amplifier As relay in is operated to the position shown, the sea ground 60 is connected to the upper terminal oi network N through the right hand contacts oi? relay and to conductor '7 through the intermediate contacts of relay 15 and the right hand contacts of relay 8. The left hand contacts oi? relay 15 which control the operation of. relay 1e are again opened.

(am 21 continues to rotate slowly for a period oi? a 'iproxil'natoly ten seconds until it reaches the point where it engages the right hand contact spring of key 20, thus completing energizing circuits for relays 8, 13 and 85. As relay 8 is operated, contact spring 51 moves out of engagement with spring 55, thus (lisconnecting cable conductor 7 from the intermediate contacts of relay 1.5 which in turn are connected to the sea earth. Spring 51 next engages contact thereby connecting cable conductor 7 to sending con denser K which remains grounded until the armature of relay 8 has moved a sullicicnt distance to separate springs 50 and 5st and thereby remove the ground connection. As relay 13 is operated, the lower contacts are engaged thereby connecting the operating windings of relays 9 and 10 with the operating loop 3, at. The upper left hand contacts of relay 13 are opened. and lamp tic-- cordingly extinguished. Upon the operation of relay 35 the lower contacts of this relay associate the sending mechanism l with its transmitting relays 4:2 and and sending battery 46 with the operating loop 3, 4-. The upper contacts of this relay are moved in a position to extinguish receiving lamp 38, leaving lamp 3'? lit.

The system is now once more in condition for transmitting messages. Transmitter T and its associated apparatus is connected over the ope 'ating loop 3, a with sending relays 9 and 10 which, upon operation, send positive, negative or zero impulses through the sending condenser K over cable conductor '7 to the distant station. The input circuit oi network N is grounded by the contacts of relay 15 and amplifier S is short circuited by relay 16. Lamps 23 and 37 are lighted and lamps 24: and 38 are unlighted, indicating that the apparatus at both stations is in position for transmitting messages.

lVhile this invention has been described as embodied in a submarine cable system, certain aspects oi the invention are of broader application. This has been borne in mind in drafting the claims.

What is claimed is:

1. In a signaling system, a transmitting conductor having a pair of stations located at one end thereof, transmitting and receiving mechanisms at one of said stations, and means operable at either of said stations to associate either the transmitting mechanism or the receivin g mechanism with the conductor.

In a signaling system, a transmitting conductor having a pair of stations located at one end thereof, transmitting and receiving mechanisms at one of said stations, means operable at either of said stations to associate either the transmitting or the receiving mechanism. with the conductor and means for grounding the conductor when switching from the sending to receiving positions.

3. In a signaling system, a transmitting conductor having a pair of stations located at one end thereof, transmitting and receiving mechanisms at one of. said stations, SWitCllillfZ; means operable at either of said stations to connect either the transmitting or the receiving mechanism with the conductor, means for grounding the conductor when switching from the sending to the receiving positions, and means for short circuiting the amplifier during a portion of the switching interval.

4. In a signaling system, a cable having a pair of stations located at one end thereof, transmitting and receiving mechanisms at one of said stations, an amplifier and sending condenser at the other of said stations, means operable at either station for disconnecting the transmitter with its associated sending condenser from the cable and connecting thereto the receiving mechanism and its associated amplifier.

5. In a signaling system, a cable having a pair of: stations located at one end thereof, transmitting and receiving mechanisms at one of said stations, an amplifier and sending condenser at the other of said stations, and means operable at either of said stations {or sequentially disconnecting the transmit.-

1 ing the sending condenser, grounding. the

cable, and connecting the receiver and its associated amplifierto the cable.

6., In a signaling system, a cable. having a. palr' of stations located atone end thereof, transmitting and receiving mechanisms atone of saidvstations, an amplifier and sending condenser at theother of said stations, means operable at either of said stations for sequentially disconnecting the transmitting mechanism from the cable, short circuiting the sending condenser, grounding the cable and connecting the receiving mechanism and its associated amplifier to the cable, and means for short circuiting the amplifier during the switching operations.

7 In a signaling system, a cable having a pair of stations located at one end thereof,

7 a transmitting and a receiving mechanism located at one of said stations, an ampli fier and a sending condenser located at the other of said statlons, mea-nsoperable at either {of said stations for automatically connecting the transmitter with an associated sending condenser to the cable or for connecting thereto the receiver with its associated amplifier, and means for indicating which apparatus is connected to the cable.

8. In a signaling system, a cable having a pair of stations located at one end thereof, a transmitting and a receiving mechanism located at one of said stations, an amplifier and a sending condenser located at the other of said stations, means operable at either of said stations for automatically connecting the transmitter with its associated sending condenser to the cable or for connecting thereto the receiver with its associated amplifier, and indicating means at each of said stations to indicate the position of the switching means.

9. In a signaling system, a loaded cable,

having a pair of stations located at one end thereof, a receiving mechanism, a transmitting mechanism, and common means operable at either of said stations for disconnecting one of said mechanisms from the cable and connecting the other thereto, provision being made for grounding the cable between said operations for a period of time sufficient to drain off the major portion of the potential energy resulting from the previous transmission of signals.

10. In a signaling system comprising a cable and a pair of stations associated with one end of the cable, transmitting and receiving mechanisms at said stations, a portion of both the transmitting and'receiving mechanisms being located at one of said stations and another portion of both said transmitting and receiving mechanisms being located atthe other of said stations, and means at each station for associating either the transmitting-or therccciving mechanisms with the cable- 11. In a signaling system, a cable having a pair of stations located at one end thereof, transmitting and receiving mechanisms located at one of said stations, and cam' operated circuit closing devices operable at either of said stations for disconnecting the transmitting mechanism from the cable, grounding the cable for a given interval of time and then connecting the receiving mechanism thereto.

12. In a signaling system comprising a loaded submarine cable having a pair of separatestations at one end thereof joined togethcr by a; second cable comprising an operating loop and a control loop, transmit ting and receiving mechanisms located at one of said stations, an amplifier and sending condenser located at the other of said sta 13. In a signaling system, a transmission conductor, transmitting and receiving mechainsms located at one terminal of said conductor and cam operated circuit closing devices operable at said station for disconnecting the transmitting mechanism from the conductor, grounding the conductor for a given interval of time and then connecting the receiving mechanism thereto.

14. In a signaling system, a transmission conductor, transmitting mechanism including a sendingcondenser and receiving mechanism including an amplifier, all located at one terminal of said conductor, and means operable at said terminal for sequentially disconnecting the transmitting mechanism from the conductor, short circuiting the sending condenser, grounding the conductor and connecting the receiver and its associated amplifier to the conductor. 7

15. In a signaling system, a transmission conductor, transmitting mechanism includmg a sending condenser and recelvlng mechanism including an amplifier, all located at one terminal of said conductor, means operable at said terminal for sequentially disconnecting the transmitting mechanism from the conductor, short circuiting the sending condenser, grounding the conductor and connectingthe receiving mechanism and its associated amplifiento the conductor, and means for short circuiting the amplifier during the switching operations. 16. In a signaling system, a transmissio conductor, transmitting mechanism including a sending condonser and roveivin 1110(i1- anism in'ilnding'r an amplifier ail 10 rated at one terminal of said conductor, means operable at said terminal for automaticmlly connesting the transmitting mechanism with the associated sending condense]? to the conductor or for connecting" thereto the rcceiw ing mechanism with its associated amplifier, and 111mm: for indicating whichapparatus connected to said conductor.

In Witnoss whereof, I hereunto subscribe my name this 2d day of October A. D. 192%. f

GEORGE A. LOCKE. 

